4820 is no longer produced in standard off the shelf round bar sizes . There is limited stock remaining in the industry.
Alloy 4820 is a Nickel/Moly alloy with extremely good toughness, stability in heat treatment, and case depth. It is a low carbon case hardening alloy that has a tough, ductile core. It is used for applications where toughness and shock resistance is critical such as mining equipment and hand tools. 4820 is produced to BQ-Bearing Quality for the most demanding applications.
Common applications include bushings, wear pins, sprockets, gears, pinion Shafts.
UNS# G48200 Nickel molybdenum alloy steel
ASTM A-29 GENERAL REQUIREMENTS FOR CARBON & ALLOY BARS, WROUGHT & COLD-FINISHED
ASTM A-322 STEEL BARS, ALLOY, STANDARD GRADES STEEL BARS, ALLOY, STANDARD GRADES
ASTM A-331 STEEL BARS, ALLOY, COLD-FINISHED STEEL BARS, ALLOY, COLD-FINISHED
ASTM A-519 SEAMLESS CARBON & ALLOY MECHANICAL TUBING
ASTM A-535 SPECIAL-QUALITY BALL & ROLLER BEARING STEEL SPECIAL-QUALITY BALL & ROLLER BEARING STEEL
ASTM A-711 STANDARD SPEC. FOR STEEL FORGING STOCK STANDARD SPEC. FOR STEEL FORGING STOCK
ASTM A-752 GENERAL REQUIREMENTS FOR WIRE RODS & COARSE WIRE, ALLOY STEEL
J1397 ESTIMATED MECHANICAL PROPERTIES & MACHINABILITY OF STEEL BARS
J404 CHEMICAL COMPOSITIONS OF SAE ALLOY STEELS
J412 GENERAL CHARACTERISTICS & HEAT TREATMENTS OF STEELS GENERAL CHARACTERISTICS & HEAT TREATMENTS OF STEELS